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arXiv · 2208.13261

Resonance mediated by fermions in kink-antikink collisions

Dionisio Bazeia·João G. F. Campos·Azadeh Mohammadi
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Abstract

We investigate generalizations of the $\phi^4$ and sine-Gordon models, including interactions with Dirac Fermions. We observe new resonance phenomena by taking the fermion back-reaction into account. First, we show that the vibrational mode responsible for the resonance structure of the $\phi^4$ model has the same frequency as the energy of the fermion excited state when the back-reaction becomes more significant. Second, we consider the sine-Gordon model with the addition of a fermion field and find that a resonant structure appears, despite the absence of a scalar vibrational mode. The vibrational frequency of the mode responsible for the exchange mechanism is again the energy of the fermion excited state. Therefore, we find a new type of resonant energy exchange mechanism which is mediated by fermions.

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Dionisio Bazeia, João G. F. Campos, Azadeh Mohammadi. 2022-08-28. Resonance mediated by fermions in kink-antikink collisions. https://doi.org/10.1007/jhep12(2022)085

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